1. Field of the Invention
The present invention relates generally to liquid transfer systems for transferring liquid from one container to another. More particularly, the liquid transfer system of the invention permits the safe and efficient transfer of liquid from a container sealed by a frangible seal to a drum type container of the character having a coupler operated extractor valve.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
A number of different types of reusable systems for the storage, shipment and transport of liquid formulations have been suggested. One of the most advanced of such systems was developed by and is presently commercially available from Micro Matic, Inc. of Northridge, Calif.
The Micro Matic system is basically a two-part system which comprises a coupler operated extractor valve which is interconnectable with a conventional drum via existing threaded connections and a cooperating coupler which is operably coupled with the extractor valve to allow drum emptying through the use of a separate pumping system. The extractor valve apparatus which can either remain with the drum after emptying, or can be removed for drum processing, includes a valve body and a down tube connected to the valve body which extends to the bottom of the drum to permit the complete transfer of liquid from the drum.
Recently a need has developed to safely transfer liquids, including hazardous liquids, from containers such as plastic jugs that are sealed by frangible seals, to conventional drums of the character having coupler operated extractor valves. Problems related to such transfers include providing means for safely rupturing the frangible seal of the plastic jugs and means for operating the coupler operated extractor valve of the drum in a manner to permit the liquid to be safely transferred from the plastic jug into the reservoir of the drum. As will be better understood from the discussion which follows, after carefully analyzing these problems the present inventor solved them by providing an elegant but relatively simple closed system that includes a modified coupler which, upon normal operation, safely ruptures the frangible seal of the plastic jug and at the same time opens the coupler operated extractor valve on the drum so as to permit fluid to flow freely from the plastic jug into the reservoir of the drum. Without the present invention, in order to transfer liquids from a sealed plastic jug to the reservoir of a drum having a coupler-operated extractor valve, it would be necessary to remove the extractor valve from the drum, manually rupture the foil seal on the plastic jug and then pour the contents of the plastic jug into the drum. Such a procedure would be not only time-consuming but extremely dangerous if the liquid in the plastic jug was a hazardous liquid.